Ultra SCSI Fast20 OverClock

BlueSCSI can support the Ultra SCSI Fast20 SCSI timings with an overclock.

Warning

While overclocking a Pi Pico is generally safe - you do so at your own risk.

Prerequisites

You will need an SCSI card that supports Ultra SCSI (Fast20) with a 50 pin connector or an HD68 to 50 pin adapter.

Flash the Alpha uf2 file here: https://github.com/BlueSCSI/BlueSCSI-v2/actions/runs/12614338879/artifacts/2386416061

Working

• Adaptec 2940W PCI (Mac, Pico1)
  • 16MB/sec Read, 10MB/sec Write
• Adaptec 2940UW PCI (Win7 32, Pico1)
  • 9.5MB/sec Read, 5.35MB/sec Write
  • Note: you must use the 68-pin connector to get 20MB/sec negotiation
• Adaptec 2940UW PCI (Win98 SE, Pico1)
  • 16.3MB/sec Read, 7.2MB/sec Write
  • Note: you must use the 68-pin connector to get 20MB/sec negotiation
• Symbios 22801 PCI (WinXP, Pico2)
  • 12MB/sec Read, 4MB/sec Write
• SGI O2 via 50p CDROM connector (IRIX 6.5.30, Pico2)
  • 16MB/sec Read, 8MB/sec Write

Unstable

• Adaptec 2940U2B PCI (WinXP, Pico2)

Not working

Enable

[SCSI]
SpeedGrade="TurboA"
MaxSyncSpeed=20